This section provides background information related to the present disclosure which is not necessarily prior art.
Many modern automotive vehicles, such as crossover vehicles, are available with an all-wheel drive (AWD) drivetrain that is based on a front-wheel drive (FWD) architecture. This optional drivetrain arrangement permits drive torque to be selectively and/or automatically transferred from the powertrain to both the primary (i.e., front) driveline and the secondary (i.e., rear) driveline to provide better traction when the vehicle is operated in inclement weather and on off-highway road conditions. Such AWD vehicles necessarily are equipped with a much more complex drivetrain which, in addition to the primary driveline, must include the additional components associated with the secondary driveline such as a power take-off unit and a propshaft.
In an effort to minimize driveline losses (i.e., viscous drag, friction, inertia and oil churning) associated with secondary driveline being back-driven when no drive torque is transmitted thereto, it is known to incorporate a disconnect system that is configured to uncouple components of the secondary driveline such as, for example, the rear wheels or the rear differential from the remainder of the secondary driveline. We have found that portions of the disconnect systems provided by some suppliers are not capable of completely disconnecting in a relatively quick manner and as such, there are some situations where they will continue to transmit some (relatively small) amount of rotary power at time where the disconnect system is being operated to inhibit the transmission of rotary power. Accordingly, there remains a need in the art for an improved disconnectable driveline for use in an AWD vehicle.